Sheet-metal silo-roof.



L F. MCGAFFEE.

SHEET METAL SILO ROOF. APPLICAHON FILED MAR. z. 1916.

Patefited May 28, 1918'.

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JAMES F. MCGAFFEE, 0F DES MOINES, IOWA.

SHEET-METAL SILO-ROOF.

Specification of Letters Patent.

Patented May 28, 1918.

Application filed March 7, 1916. Serial No. 82,652.

To all whom it may concern:

Be it known that I, JAMEs F. MoGArrnE, a citizen of the United States, and resident of Des Moines, in the county of Polk and State of Iowa, have invented a certain new and useful Sheet-Metal Silo-Roof, of which the following is a specification.

The object of my invention is to provide a sheet metal silo roof of simple, durable and inexpensive construction.

More particularly, it is my object to pro vide a sheet metal silo roof of the type for covering a round silo, and inclined from its middle point downwardly and outwardly to the upper edge of the silo wall, which roof is adapted to be made in sections which may be cut from the metal in such a way as to reduce the waste of metal to a minimum.

Such a construction requires the'use of a comparatively large number of strips or pieces which must be secured together at the side edges and it is therefore a further object ofmy invention to provide such a device in which the strips are suitably secured together in such a manner'that the joints shall be raised so that the water shall flow off from the joint portions to the flat portions which form a trough to carry the water off the roof.

A further object is to provide such a roof having sections so made andoassembled as to allow for variations in the positions of the rafters and to allow for expansion and contraction of the silo wall andthe roof.

Still a further object is to provide such a roof in which the sections which are secured to the rafter or other solid supports may be provided with means for covering the nails or other means for securing the strips of the metal roof to the rafters.

Still a further object is to provide such a roof in which the sections have extensions at their lower edges, so formed as to reduce to a minimum the amount of material used, and adapted to carry an annular ring for preventing water from getting into the silo from the edge of the silo wall.

Still a further object is to provide simple and novel means for connecting the metal strips at their upper ends with a suitable support, and for mounting a suitable ventilating device in the upper central portion of said roof.

My invention consists in certain details, in the construction,combination and arrangeed in the channel.

Fig. 3 shows a detail, sectional view of part of the metal roof.

Fig. 4 shows a plan view of the blank frpim which the roof sections are formed, an

Fig. 5 shows a detail view of a part of the lower edge of the roof.

In the accompanying drawings I have used the reference numeral 10 to indicate the upper portionof a silo wall. My improved metal roof comprises a plurality of sections, which are preferably made up as follows: The sections 11 are cut with one straight longitudinal edge 12 and one in clined longitudinal edge 13. In the actual construction ofothe sections they are really out out in pairs, in which the longitudinal edges 12 are at the outside of the respec; tive members of the pairs whilethe adjacent edges are the inclined edges 13, shown in Fig. 4. At the wide end of each section notches are cut away at the corners to allow for bending the side'edges as herein described, and to leave the portion 13" hereinafterreferred to.

In the further description of the roof 'I have for convenience used the term roof section,to describe the'member made up of two section members, shown in Fig. 4. It will be seen that each roof section is made from a rectangular metal blank with a min imum waste of material. The right hand section member 11 is turned over and placed with its wide end adjacent to the wide end of the left hand section 11 and with the two edges 12 together. The portion of one section member 11, adjacent to one of the edges 12, is then inclined upwardly and outwardly at 14, as shown in Fig. 3, then downwardly and outwardly, as shown at 15, then downwardly and inwardly, as shown at 16, then upwardly and inwardly as shown at 17,

- 2% and a similar horizontal the portions 15, 16 and 17 forming a channel. The portion of the other member 11 adjacent to its edge 12 is then inclined upwardly and outwardly at 18, then upwardly and inwardly at 19, then downwardly and inwardly at 20. The parts just mentioned are bent simultaneously so that the channel formed by the members 15, 16 and 17 receives the portion 20 and the channel formed by the portions 18, 19 and 20 receives the portion 17., as clearly shown in Fig.

The essential features of the method and construction for connecting the members 11 of each roof section are the forming of a comparatively watertight joint, arranged that the joint portions are raised above the level ofthe body portions of the section members 11, to afford properdrainage, and to prevent the discharge of water through the roof sections at the joints.

At the upper central portion of the roof, I provide an annular channel 21 of flexible material so that it can be radily sprui'ig orv bent, which channel opens outwardly and the flanges of which. are inclined slightly downwardly according to the pitch of the roof to be pitched upward, as shown. in Figs. 1 and 2.

In the construction of the roof, the upper ends of the rafters are properly beveled to lit into the channel 21, as shown in Fig. 2. A plurality of said rafters are mounted in the channel andisecured thereto in any suitable way. T he lower ends of the rafters are provided with notches 23 in their lower sur face to rest upon the upper edge of the silo wall.-

Owing to the fact that the annular'channel 21 is of comparatively small diameter, the number of rafters which can be employed is limited. It will therefore be seen that there is a s ving of metal at the ends of the members 11 for making a joint be tween each rafter, and the oint hereinbefore described is therefore located between the rafters. The edges 12 of one section memher are formed with upwardly and outwardly bent port-ions 2d at one side and then with horizontal portions 25, and then with avertical strip or portion 26. The adjacent inclined edge of the adjacent section member of thenext section is formed with a similar upwardly and outwardly bent portion portion The lastdescribed portion rests upon one of the rafters 22 and the portion 25 which has formed on it the portion 26 is spaced above the portion 25 which rests on the rafter. The two portions 25 are then secured to the rafter by nails 27 or other suitable means when the portion 26 can then be hammered down over the nails, as shown in Fig. ,5. At the center of the silo roof is a cylinder 29, the lower end of which is received within the annular channel 21. Formed on the outer surface of the cylinder 29, above the lower end of said cylinder, is an annular downwardly QXLQlIdlIIg flange 30. The upper ends of the roof sections are inserted beneath the flange, 30, as shown in Fig.1. Mounted on the upper end of the cylinder 29 is a spaced cover 31, shown in Fig. 1. I

The extensionslil at the lower ends of the roof sections are bent downwardly, as shown in Figs. 1 and 5 and the lower edges of said extensions are bent to form {upwardly opening channels to receive the .edgeof the downwardly opening channel 33,

mentioned so that if the silo wall should not be absolutely true, the members 22 may be moved to lit the silo wall and the annular channel 21 will be sprung to proper position.

The portion 25 of the roof sections are greater in width than the width of the rafters 22, so that if the positions of the rafters vary somewhat, for any reason, the portions 25 will still rest on the tops of the rafters. Such construction is important in view of the fact that the ordinary silo wall usually varies from a true circle owing to imperfections of the parts or difficulties and carelessness in construction. 7

The cylinder 29 and cover 31 furnish ventilation and at the same time complete the waterproof joint at the apex of the roof.

It will be understood that some changes may be made in the details of the construction of my silo roof and it is my intention to cover by my application any such changes which embody my invention and are included within the scope of my claims:

I claim as my invention:

1. In a silo roof construction, the combination of an annular flexible or springing channel, the flanges of saidchannel extend.- ing outwardly and downwardly, a series of roof beams provided with means near their lower ends for engaging a side wall, the up per ends of said beams being designedto be inserted in and secured to said channel, the flexibility or springing tendency of the channel providing means whereby any irregularities in contour of the silo wall may be compensated for by the flexible or springing channel without changing the position of the wall relative to the'roof beams, waterproof roofing extended over said beams, and a ventilating cylinder having between its upper and lower ends an outwardly and downwardly extending flange and being designed to be inserted in. the annular channel with its flange overlapping the roofing and forming a water shedding joint even though the annular channel is bent or sprung considerably out of a true circle.

2. In a silo roof construction, the combination of an annular springing or flexible channel, the flanges of said channel extending outwardly and downwardly, a series of roof beams provided with means near their lower ends for engaging a side wall, the upper ends of said beams being designed to be inserted in and secured to said channel, the flexibility 0r springing tendency of the channel providing means whereby any irregularities in contour of the silo wall may be compensated for by the flexible or spring,- ing channel without changing the position of the roof beams relative to the wall, waterproof roofing extended over said beams, a ventilating cylinder having between its upper and lower ends an outwardly and downwardly extending flange and being designed to be inserted in the annular channel with its flange overlapping the roofing z) and forming a water shedding oint even though the annular channel is bent or sprung considerably out of a true circle, and

means for connecting the flange of the ventilating cylinder to the beams for strengthening and firmly supporting the flexible annular channel.

3. A silo roof comprising a pluralit of spaced roof beams, and a plurality of exible roof sections having each side edge secured to a roof beam, the roof sections having a longitudinal portion adjacent to each side edge inclined downwardly and laterally and a longitudinal central V shaped raised rib adapted to strengthen the roof section longitudinally and to spread as the roof beams move toward or from each other.

l. In a silo roof adapted to be placed on a substantially circular silo, a plurality of roof beams having a notch at a predetermined point adjacent to their outer ends whereby they may be secured to the silo wall, a pliable collar, and means for secur ing the inner ends of said beams to said collar.

Des Moines, Iowa, August 12, 1914.

JAMES F. MCGAFFEE.

Witnesses:

L. ROBINSON, A. SHERMAN.

Copies of this patent may be obtained for five cents eaclnby addressing the Commissioner of Patents.

Washington, D. 0. 

